feat(sql): support date types and calendar interval expressions

[Selvomega]

Why

SQL data-quality checks using CAST(... AS DATE) or INTERVAL '30' DAY failed during lowering because the canonical IR lacked date and calendar-interval types.

What and how

Add DataType::Date, DataType::Interval, and a calendar-interval literal carrying months, days, and nanoseconds. Bridge Arrow date and interval types into these representations and preserve temporal result types through date/timestamp shifts and interval negation. Normalize typed Arrow date literals to date casts and explicitly reject multi-column COUNT(DISTINCT ...), whose tuple semantics the IR cannot represent. Reject fixed-duration subtraction before lowering, including inside predicates, CASE branches, and sort expressions, because the IR cannot preserve its unit.

Before this PR

l_receiptdate <= l_shipdate + INTERVAL '30' DAY failed with an unsupported interval scalar; CAST('1992-01-01' AS DATE) failed with unsupported Arrow Date32.

After this PR

Both expressions lower successfully. Typed Arrow date literals also lower as date casts. Date shifts retain Date, timestamp shifts retain Timestamp, and -CAST('1 day' AS INTERVAL) retains Interval. Unsupported d - d duration results fail explicitly even in expressions such as (d - d) IS NULL.

Verification

• Regression tests reproduced nested-duration acceptance and interval negation being typed as Float64; both pass after the fixes.
• All 1,118 workspace tests pass, including doc tests. Regression tests also reproduce and fix typed Arrow date-literal rejection and silent loss of composite DISTINCT keys.
• The new TPC-H data-quality corpus uses actual Date columns and lowers 47 of 50 checks, with the exact rejected IDs and reasons pinned; the BGP corpus now lowers 154 queries, up from 152.
• The packet-trace corpus lowers 61/70 queries; nine composite distinct counts now fail explicitly instead of silently counting the first key.
• cargo +1.98.0 test --workspace --locked, workspace Clippy with warnings denied, and formatting checks pass.
• Vendored MetricsQL baseline verification passes. The external-consumer script is blocked locally: it hardcodes cargo +stable, whose installed toolchain is missing rustc.

Limitations

Arrow Date64 normalizes to Date and registers back as Date32. Fixed-duration results remain unsupported. Composite distinct counts and the two TPC-H correlation checks remain unsupported. Verification covers planning/lowering, not database execution; performance measurements and screenshots are not applicable.

Closes #416
Closes #418

[Copilot]

🟡 Changes recommended

Unresolved date/interval handling and data-quality coverage issues must be addressed before approval.

Get a fresh assessment by requesting another Copilot review.

Pull request overview

Expands SQL and pre-ASAP support for date/interval types and adds TPC-H data-quality coverage.

Changes:

• Adds date and interval type/scalar handling.
• Updates temporal expression inference and SQL type bridging.
• Adds DQC and workload coverage.

File summaries

File	Summary	Final review notes
crates/types/src/pre_asap/schema.rs	Adds Date and Interval types.	—
crates/types/src/pre_asap/query_expr.rs	Adds temporal arithmetic inference and tests.	Negative interval arithmetic can infer Float64 (moderate, 2 votes).
crates/types/src/pre_asap/expr_ir.rs	Adds interval scalar representation.	—
crates/frontend-sql/tests/data_quality_check/tpch_deequ.rs	Adds TPC-H lowering coverage.	Exercise date columns directly and assert the exact rejected query set (moderate, 2 votes; moderate, 1 vote).
crates/frontend-sql/tests/data_quality_check/data/tpch_deequ_queries.sql	Adds the DQC query corpus.	Composite COUNT(DISTINCT ...) may count only the first column (critical, 1 vote).
crates/frontend-sql/tests/bgp_jan2024_workload/bgp_jan2024_workload.rs	Updates interval-related tally expectations.	Update the stale explanatory rationale (nit, 1 vote).
crates/frontend-sql/src/sql/types.rs	Bridges date and interval SQL types.	Date literals lack lowering, and reverse interval mapping is missing (moderate, 3 votes; moderate, 1 vote).
crates/frontend-sql/Cargo.toml	Registers the integration test.	—

Review details

Suppressed comments (3)

crates/frontend-sql/src/sql/types.rs:187

• dtype_to_arrow emits an Arrow interval for DataType::Interval, but the reverse match still rejects every ArrowDataType::Interval. The comment above explicitly acknowledges that a hand-built catalog can reach this branch, so such a schema cannot round-trip and interval-typed planning paths fail with UnsupportedFeature. Add the reverse interval mapping (or reject Interval before registration) instead of exposing a one-way bridge.

            ArrowDataType::Interval(datafusion::arrow::datatypes::IntervalUnit::MonthDayNano)

crates/frontend-sql/tests/bgp_jan2024_workload/bgp_jan2024_workload.rs:204

• The tally update is inconsistent with the explanatory paragraph immediately above it: that paragraph still says the two toStartOfInterval queries fail in Other because interval conversion is unsupported, while these new expectations say both lower and Other is zero. Please update that rationale as part of this tally change so the pinned test does not document the old failure mode.

    // 152 -> 154: `ScalarValue::Interval` (this branch) converts the
    // `INTERVAL x unit` literal the two `toStartOfInterval(...)` queries
    // carry, which the note above recorded as an open companion gap.
    expect(Category::Lowered, 154);

crates/frontend-sql/tests/data_quality_check/tpch_deequ.rs:116

• This ratchet checks only the aggregate lowered == 48, so it can pass if one currently supported query starts rejecting while one of the two corr queries starts lowering (or the reverse). Since the comment promises that the two rejects are specifically corr, track the query IDs/error categories and assert that exact rejected set so the test detects coverage swaps, not just the total.

    // Coverage ratchet. The 2 that do not lower are the `corr` cells; adding a
    // binary `AggIntent` would raise this to 50.
    assert_eq!(
        t.lowered, 48,
        "SQL lowering coverage moved off the DQC ratchet: {t:?}"

• Files reviewed: 8/8 changed files
• Comments generated: 4
• Review effort level: Lite

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